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81.
Leukocyte apoptosis and its significance in sepsis and shock 总被引:12,自引:0,他引:12
Sepsis and multiple organ failure continue to be significant problems among trauma, burn, and the critically ill patient population. Thus, a number of laboratories have focused on understanding the role of altered apoptotic cell death in contributing to immune and organ dysfunction seen in sepsis and shock. Immune cells that undergo altered apoptotic changes include neutrophils, macrophages, dendritic cells, as well as various lymphocyte populations. Evidence of epithelial as well as endothelial cell apoptotic changes has also been reported. Although mediators such as steroids, tumor necrosis factor, nitric oxide, C5a, and Fas ligand (FasL) appear to contribute to the apoptotic changes, their effects are tissue- and cell population-selective. As inhibiting Fas-FasL signaling (e.g., gene deficiency, Fas fusion protein, or Fas short interfering RNA administration), caspase inhibition (caspase mimetic peptides), and/or the overexpression of downstream antiapoptotic molecules (e.g., Bcl-2, Akt) improve survival of septic mice, it not only demonstrates the pathological significance of this process but points to novel targets for the treatment of sepsis. 相似文献
82.
Mario T. Philipp Gary P. Wormser Adriana R. Marques Susan Bittker Dale S. Martin John Nowakowski Leonard G. Dally 《Clinical and Vaccine Immunology : CVI》2005,12(9):1069-1074
C6, a Borrelia burgdorferi-derived peptide, is used as the antigen in the C6-Lyme disease diagnostic test. We assessed retrospectively whether a fourfold decrease or a decrease to a negative value in anti-C6 antibody titer is positively correlated with a positive response to treatment in a sample of culture-confirmed patients with either early localized (single erythema migrans [EM]; n = 93) or early disseminated (multiple EM; n = 27) disease. All of these patients had been treated with antibiotics and were free of disease within 6 to 12 months of follow-up. Results show that a serum specimen taken at this time was either C6 negative or had a ≥4-fold decrease in C6 antibody titer with respect to a specimen taken at baseline (or during the early convalescent period if the baseline specimen was C6 negative) for all of the multiple-EM patients (P < 0.0001) and in 89% of the single-EM patients (P < 0.0001). These results indicate that a decline in anti-C6 antibody titer coincides with effective antimicrobial therapy in patients with early localized or early disseminated Lyme borreliosis. 相似文献
83.
A comparison of the sniff magnitude test and the University of Pennsylvania Smell Identification Test in children and nonnative English speakers 总被引:1,自引:0,他引:1
The sniff magnitude test (SMT) is a reliable and rapid clinical test of olfactory function that is minimally dependent on cognitive and linguistic abilities. In this study, we compared performance on the SMT and University of Pennsylvania Smell Identification Test (UPSIT) in samples of children and nonnative English speakers. Previous research has shown that these populations perform poorly on the UPSIT as compared with young, healthy U.S. adults. Such performance differences may reflect variations in memory/cognition and language/culture rather than olfactory abilities. The UPSIT scores of children and of Indian and Chinese graduate students were found to be lower than those of young U.S. adults. By contrast, these groups did not perform more poorly than U.S. adults did on the SMT. The results are consistent with findings from our studies, with the elderly showing that performance on the UPSIT, but not the SMT, is significantly correlated with measures of memory, language and other cognitive abilities. The findings highlight the utility of the SMT when evaluating the olfactory ability of the very young, older adults and people with diverse linguistic and cultural backgrounds. 相似文献
84.
Cristofori P Crivellente F Campagnola M Pasini AF Garbin U Rigoni A Tosetti M Turton J Faustinelli I Cominacini L 《International journal of experimental pathology》2004,85(2):105-114
A study has been carried out in the apolipoprotein (apo) E-deficient mouse to investigate the activity of lacidipine (a calcium antagonist with antioxidant properties) in inhibiting the development of atherosclerotic lesions; of particular interest were changes in the susceptibility of low-density lipoproteins (LDL) to oxidation. Mice receiving a Western-type diet to accelerate the development of atherosclerosis were treated orally with vehicle or lacidipine at 3 or 10 mg/kg/day for 8 weeks. Lacidipine treatment (at 3 or 10 mg/kg) had no effect on the plasma lipid profile. However, a significant (P < 0.01) dose-related reduction of 43 and 50% of the aortic lesion area in respect to vehicle-treated mice was observed. Moreover, the resistance of mouse plasma LDL to undergo lipid peroxidation was significantly (P < 0.01) increased in apo E-deficient mice treated with lacidipine. The native LDL-like particle, derived from apo E-deficient mice treated with lacidipine, contained significantly lower concentrations of malonyldialdehyde than the vehicle-treated control group (P < 0.01). After exposure to human umbilical vein endothelial cells, LDL-like particle vitamin E levels (expressed as area under the curve; AUC), were significantly higher (P < 0.01) in both the 3 and 10 mg/kg lacidipine-treated groups, in comparison with the vehicle-treated control animals. We conclude that lacidipine reduced the extent of the atherosclerotic area in hypercholesterolaemic apo E-deficient mice, and that this reduction may be associated with the capacity of the drug to decrease the susceptibility of LDL to oxidation. 相似文献
85.
Mario Sánchez-Borges Fernan Caballero-Fonseca Arnaldo Capriles-Hulett 《Annals of allergy, asthma & immunology》2005,94(1):34-38
BACKGROUND: Selective inhibitors of cyclooxygenase 2 (COX-2) are generally tolerated by patients sensitive to nonsteroidal anti-inflammatory drugs (NSAIDs) that inhibit COX-1. Valdecoxib is a new sulfonamide-containing COX-2-specific inhibitor indicated for the treatment of acute pain, osteoarthritis, and rheumatoid arthritis. OBJECTIVE: To compare the clinical tolerance to rofecoxib and valdecoxib in patients who previously developed urticaria and angioedema while taking classic NSAIDs. METHODS: Patients with challenge-proven NSAID cutaneous sensitivity were submitted to single-blinded controlled oral challenges with rofecoxib, 50 mg, and valdecoxib, 40 mg. RESULTS: Twenty-eight patients (19 females and 9 males; mean +/- SD age, 28.6 +/- 15.0 years; age range, 10-61 years) participated in this study. Twenty-two (85%) of 26 patients who underwent skin tests were atopic, as demonstrated by a clinical history of rhinitis and/or asthma plus positive immediate-type skin hypersensitivity test results. A previous exclusive cutaneous reaction pattern (urticaria and/or angioedema) had occurred in 10 patients (36%), whereas a mixed pattern of skin and respiratory symptoms had occurred in 18 patients (64%). Twenty patients (71%) were multiple reactors, and 8 patients (28%) were single reactors. In this current study, 2 patients (7%) taking rofecoxib experienced angioedema, and 1 patient (4%) taking valdecoxib experienced urticaria. CONCLUSIONS: Rofecoxib and valdecoxib can be safely used by most NSAID-sensitive patients with cutaneous reactions. Our findings suggest that isolated cross-reactions may occur in these patients, and for this reason, controlled oral provocation may be prudent when prescribing valdecoxib or rofecoxib for patients who have previously had urticaria or angioedema triggered by NSAIDs. 相似文献
86.
Arbustini E Grasso M Ansaldi S Malattia C Pilotto A Porcu E Disabella E Marziliano N Pisani A Lanzarini L Mannarino S Larizza D Mosconi M Antoniazzi E Zoia MC Meloni G Magrassi L Brega A Bedeschi MF Torrente I Mari F Tavazzi L 《Human mutation》2005,26(5):494
Marfan Syndrome (MFS) is an autosomal dominant disorder of the connective tissue due to mutations of Fibrillin-1 gene (FBN1) in more than 90% of cases and Transforming Growth Factor-Beta-Receptor2 gene (TGFB2R) in a minority of cases. Genotyping is relevant for diagnosis and genotype-phenotype correlations. We describe the FBN1 genotypes and related phenotypes of 81 patients who were referred to our attention for MFS or Marfan-like phenotypes. Patients underwent multidisciplinary pertinent evaluation in the adult or paediatric setting, according to their age. The diagnosis relied on Ghent criteria. To optimise DHPLC analysis of the FBN1 gene, all coding regions of the gene were directly sequenced in 19 cases and 10 controls: heterozygous amplicons were used as true positives. DHPLC sensitivity was 100%. Then, DHPLC was used to screen 62 other cases. We identified 74 FBN1 mutations in 81 patients: 64 were novel and 17 known. Of the 81 mutations, 41 were missense (50.6%), 27, either nonsense or frameshift mutations and predicted a premature termination codon (PTC) (33%), 11 affected splice sites (13.6%), and two predicted in-frame deletions (2.5%). Most mutations (67.9%) occurred in cbEGF-like modules. Genotype was clinically relevant for early diagnosis and conclusion of the diagnostic work-up in patients with incomplete or atypical phenotypes. 相似文献
87.
Cipriano C Giacconi R Muzzioli M Gasparini N Orlando F Corradi A Cabassi E Mocchegiani E 《Mechanisms of ageing and development》2003,124(8-9):877-886
Because of its similarity to ageing in impaired immune efficiency 48 h after surgical procedures on young partially hepatectomised mice, partial hepatectomy/liver regeneration (pHx) provides a good model for the study of inflammation in ageing. In old age, high metallothionein (I+II) (MT) sequesters a substantial number of intracellular zinc ions consequently leading to low zinc ion bioavailability for an adequate immune response. Corticosterone and IL-6 affect MTmRNA induction in inflammation and after pHx against oxidative damage. The aim of this study was to investigate the role played by MT in conferring immune plasticity in ageing and in very old age using the pHx model. 48 h after their partial hepatectomy, the crude zinc balance was negative in young, old and very old mice coupled with increased MT, corticosterone, sIL-6R and IL-6. Concomitantly, Natural Killer (NK) cell activity and IL-2 production decreased. Complete restoration of the nutritional-endocrine-immune parameters occurred 15 days from the surgical procedures in young and very old mice, but not in old or transgenic mice overexpressing MT. A significant positive or inverse correlation among nutritional-endocrine-immune parameters exists in young and very old mice, but not in old mice during liver regeneration. Since MT also affects c-myc, the gene expression of c-myc declines from 48 h to days 7 and 15 after pHx in young and very old mice, but remains constantly high in old pHx mice for the same days. This circumstance leads to the appearance of tumours in the long run in old pHx mice and survival times that are shorter than old sham controls. Because complete remodelling also occurs in IL-6 and in sIL-6R in very old mice during liver regeneration, the pre-existing inflammation is not detrimental in very old age. As such, very old mice are still responsive to large inflammation, such as pHx, thanks to correct MT homeostasis. Correct MT homeostasis, via c-myc, is therefore pivotal in both suitable liver regeneration and in conferring immune plasticity with subsequent successful ageing. High MT plays an extremely harmful role in ageing: on one hand it lowers zinc ion bioavailability levels required for immune efficiency and on the other hand it increases c-myc expression. The combination of immune depression and enhanced c-myc, via high MT, may trigger the appearance of age-related degenerative diseases. 相似文献
88.
Newman JT Surman SR Riggs JM Hansen CT Collins PL Murphy BR Skiadopoulos MH 《Virus genes》2002,24(1):77-92
A complete consensus sequence was determined for the genomic RNA of human parainfluenza virus type 1 (HPIV1) strain Washington/20993/1964 (HPIV1 WASH/64), a clinical isolate that previously was shown to be virulent in adults. The sequence exhibited a high degree of relatedness to both Sendai virus, a PIV1 virus recovered from mice, and human PIV3 (HPIV3) with regard to cis-acting regulatory regions and protein-coding sequences. This consensus sequence was used to generate a full-length antigenomic cDNA and to recover a recombinant wild-type HPIV1 (rHPIV1). Interestingly, the rHPIV1 could be rescued from full-length antigenomic rHPIV1 cDNA using HPIV3 support plasmids, HPIV1 support plasmids, or a mixture thereof. The replication of rHPIV1 in vitro and in the respiratory tract of hamsters was similar to that of its biologically derived parent virus. The similar biological properties of rHPIV1 and HPIV1 WASH/64 in vitro and in vivo, together with the previous demonstration of the virulence of this specific isolate in humans, authenticates the rHPIV1 sequence as that of a wild-type virus. This rHPIV1 can now be used to study the biological properties of HPIV1 and as a substrate to introduce attenuating mutations for the generation of live-attenuated HPIV1 vaccine candidates.An erratum to this article can be found at 相似文献
89.
Outbreak of Saccharomyces cerevisiae subtype boulardii fungemia in patients neighboring those treated with a probiotic preparation of the organism 总被引:5,自引:0,他引:5 下载免费PDF全文
Cassone M Serra P Mondello F Girolamo A Scafetti S Pistella E Venditti M 《Journal of clinical microbiology》2003,41(11):5340-5343
We report an outbreak of Saccharomyces cerevisiae subtype boulardii fungemia among three intensive care unit roommates of patients receiving lyophilized preparations of this fungus. The fungemia was probably due to central venous catheter contamination and resolved after fluconazole treatment. The need for stringent application of proper hygiene when using a probiotic preparation of this organism is emphasized. 相似文献
90.
Susceptibility testing of fluconazole by the NCCLS broth macrodilution method, E-test, and disk diffusion for application in the routine laboratory 总被引:30,自引:0,他引:30 下载免费PDF全文
Vandenbossche I Vaneechoutte M Vandevenne M De Baere T Verschraegen G 《Journal of clinical microbiology》2002,40(3):918-921
Antifungal susceptibility testing may be an important aid in the treatment of patients with life-threatening yeast infections. In order to establish the suitability of different susceptibility test methods for fluconazole with yeasts, the Rosco tablet and the E-test were compared with the gold standard NCCLS broth macrodilution method for 106 yeast strains. These included 102 clinical isolates of Candida spp., including Candida glabrata (n = 30), Candida albicans (n = 20), Candida tropicalis (n = 13), Candida parapsilosis (n = 10), Candida krusei (n = 8), plus Cryptococcus neoformans (n = 3), Saccharomyces cerevisiae (n = 2), and 16 strains belonging to other Candida spp. Four American Type Culture Collection strains of Candida were included as quality controls. The NCCLS method was found to be too complex and labor-intensive for routine testing. The E-test is an accurate alternative, but experience in determining MICs and careful attention to procedural details are critically important. The Rosco tablet showed the best agreement with the NCCLS reference method, especially when newly established breakpoints of R < or = 10 mm and S > or = 21 mm were used. 相似文献